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HILLMAN 5/16 in. D X 3-1/2 in. L Hot Dipped Galvanized Steel Hex Bolt 50 pk

HILLMAN 5/16 in. D X 3-1/2 in. L Hot Dipped Galvanized Steel Hex Bolt 50 pk

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Support American manufacturers + independent hardware retailers in one purchase.

Hillman 5/16 in. diameter x 3-1/2 in. long hex bolts in a hot-dipped galvanized finish are built for outdoor performance and long-term durability. This 50‑pack (boxed) gives you re…

Hillman MPN 811554 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $36.99. Our online price is $40.99.
$40.99
Includes free shipping on orders over $75 · $8.99 standard below
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About Product Overview

Hillman 5/16 in. diameter x 3-1/2 in. long hex bolts in a hot-dipped galvanized finish are built for outdoor performance and long-term durability. This 50‑pack (boxed) gives you reliable fasteners for decks, fences, sheds, and other exterior wood projects.

Why these hex bolts stand out

  • Diameter and length: 5/16 in. diameter and 3-1/2 in. long provide substantial bite for strong wood-to-wood or wood-to-metal connections.
  • Coarse thread: Optimized for easy driving into wood, reducing the need for extensive pre-drilling while delivering solid grip.
  • Finish and durability: Hot-dipped galvanized coating delivers superior corrosion resistance in outdoor environments, resisting rain, humidity, and salt air.
  • Grade 2 steel: A dependable, economical choice for general purpose fastenings where moderate strength and wear resistance are sufficient.
  • Packaged convenience: 50 bolts per boxed package for quick project planning and organized storage.

Ideal use cases

  • Deck construction and repairs: securing joists, rails, and posts with confidence in outdoor conditions.
  • Fence installations: durable fasteners for gate frames and fence rails where weather exposure is a factor.
  • Outdoor sheds, pergolas, and garden structures: dependable hardware that resists rust over time.

Installation tips for best results

  • Pre-drill pilot holes to minimize wood splitting, especially near edges or when working with hardwood.
  • Use with washers and nuts as needed to achieve a secure, load-bearing connection.
  • Aim for steady, even tightening to avoid stripping threads and to maintain the integrity of the galvanized coating.

Specifications at a glance

Brand: Hillman • Product Type: Hex Bolt • Finish: Hot Dipped Galvanized • Grade: 2 • Head Diameter: 5/16 in • Length: 3-1/2 in • Material: Steel • Thread Type: Coarse • Packaging: 50 per box

The Details Specifications

Brand Hillman
SKU 54003
UPC 008236132151
Unit 0
Case Pack Quantity 2 per case
Retail Unit Quantity 1
Unit of Measure 50 BX
Dimensions (L × W × H) 4 × 4 × 4
Weight 5 lbs
Cubic Feet 0.1016 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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